The 'Cross-Border' Tornado Outbreak of 24 August 2016 - Analysis of the Two Tornadoes in Ontario

An unusual late-season tornado outbreak occurred in the afternoon and evening hours of August 24th, 2016. A total of 22 tornadoes developed across Indiana and Ohio, causing damage rated up to EF-3 on the Enhanced Fujita Scale.

Lesser known is that two additional tornadoes developed in the Windsor, Ontario area – immediately east of the US-Canada border but well northeast of the locations of the US tornadoes. The tornadoes caused damage to residential neighborhoods and industrial areas and four injuries, but no fatalities. An engineering analysis of selected structural damage will be presented.

The first tornado occurred in association with a rapidly developing thunderstorm and was rated EF-1. After a brief interlude, the same storm produced a second tornado rated at EF-2. There is some evidence to suggest that the tornadoes did not develop via the typical supercell tornadogenesis process. The thunderstorm and the first tornado developed nearly simultaneously. Also, DTX NEXRAD radar indicated that all rotation was confined to a region below 10 kft – with the strongest rotation below 5 kft – while storm echo tops reached near 50 kft. Possible explanations for the unusual development of this storm and its associated tornadoes will be provided.